Founded in 1913, Cimco Refrigeration has installed ice-making equipment in over 4,500 arenas including new NHL rinks in Miami, Chicago, Montreal, Boston, St Louis and Ottawa. The "preferred supplier" to the NHL was chosen to install the ice-making equipment in the Air Canada Centre.

Building and installing the ice making equipment for the new Air Canada Centre was the responsibility of Cimco Refrigeration, on e of the country's oldest refrigeration companies. Founded in 1913, the company has manufactured and installed the ice making equipment in over 4,500 arenas, including new NHL rinks in Miami, Chicago, Montreal, St. Louis, Philadelphia, Ottawa and Boston.

The company has even exported its expertise to England, where they recently installed ice-making equipment in a new arena for the London Knights of the UK super league.

Originally known as the Canadian Ice Machinery Company, its name was shortened to Cimco in 1967, when the company was purchased by Toromont Industries Inc., its parent company.

Cimco's expertise has allowed it to attain the status of preferred ice rink equipment supplier to the NHL. That status, among other things, allows the company to use the trademark NHL logo on its letterhead. The company also co-authored the NHL's minimum refrigeration specifications for new NHL arenas.

At the Air Canada Centre Cimco installed an ammonia-based refrigeration system, which cools ethylene glycol through a heat exchanger. The chilled glycol, which has a lower freezing point than water, is pumped into about 55,000 feet of steel pipe embedded in the concrete floor. The cold fluid freezes the floor, which in turn freezes water sprayed onto the concrete floor.

While similar systems are used in arenas across North America, David Sinclair, a contract sales representative at Cimco explains, the requirements for an NHL facility like the Air Canada Centre are much higher than they would be for a community arena.

For community arenas the floor tubing typically be polyethylene, but for NHL rinks, the specifications call for steel pipes as steel offers a higher heat transfer. Since the pipes are embedded in concrete and the glycol has a rust inhibitor added to it, there's no danger or corrosion, says Sinclair.

The pipes have a one-inch inside diameter and are installed on four inch centres across the length of the 85 x 200-foot rink. The pipes comes in 40-foot lengths that are welded together on site.

A second difference is the amount of power required to run the compressor. Where a community arena might have a 120 horse power compressor, the Air Canada Centre's compressor is 375 horse power, or three times the size. That should allow the Air Canada Centre's ice makers to make a sheet of ice in about 24 hours.

Sinclair says the length of time it takes to make a sheet of ice depends on the temperature at which the glycol is sent out and haw hard the ice-maker want the ice to be. For example, hockey players like to skate on harder ice, whereas figure skaters like softer ice. To accommodate those preferences NHL systems operate at a much higher tonnage and at lower temperatures than you would find in a community arena.

The lower temperatures also accommodate the higher radiant heat loads that are caused TV lighting, and the heat generated by 21,000 fans in the bowl. The extra radiant heat load doesn't make it more difficult to make ice, Sinclair says, you just need more equipment with larger capacity.

As the Air Canada Centre is a multipurpose facility, the ice must either be taken out, or protected when basketball games and concerts are scheduled. The owners have chosen to maintain the ice by placing an insulated floor over it.

Sinclair says some facilities, like Madison Square Gardens in New York, actually take ice out between events, but by far the most common practice is to simply cover the ice.

Most arenas like the Air Canada Centre find that it's expensive and time consuming to keep removing and replacing the ice surface. "You want to try to maintain it ads efficiently as possible and placing an insulated board on top will do the job just as will," says Sinclair.

The Air Canada Centre will also have the first refrigeration system in an NHL arena to use both screw compressors and a plate-frame heat exchanger to chill the glycol.

"If you go into any typical ice rink you wouldn't likely see a plate frame. They've become more popular in the past 8 to 10 years, but in terms of NHL rinks, its the first. In Ottawa, for example, we used screw compressors and shell and tube heat exchangers."

The advantage is the plate-frame heat exchanger is smaller and reduces the refrigerant system charge by half. It's made out of 316 ss (stainless steel), to prevent corrosion.

"It's much thinner and the surface area is tremendous because of the dimple plate, so the heat exchanger becomes much smaller," says Sinclair.

Cimco was also responsible for pouring the arena's concrete floor. As you might expect the concrete is a little harder than normal, about 35 mpa, with a non-metallic surface hardener on top. The concrete is laid to a depth of six inches in one continuous pour. "There are no stoppages, no expansion joints, no saw cuts - it's one big mass of concrete and the floor is finished to within plus or minus five mm," says Sinclair.

And what would happen if the floor ever settled? The answer, says Sinclair, is simple. "It won't settle. The floor is compacted to 95 per cent standard proctor density to prevent that".